There are many excellent java games out there, that are not on JGO, I along with other moderators will be putting showcase worthy games on this board, this is not my game but it is very cool, so if the original author is a member here please feel free to introduce yourself.
“Highnoon” is a wild west shooting game originally released on the C64 in 1984 by Ocean Software. It is based on the 1952 classic western movie of the same name.
I completely remade it and added some cool stuff like horse-thieves, sound effects, particle effects for dust and smoke, character shadows, reloading of the gun, and also tumbleweed (really, a western game should not be without tumbleweed).
It also features an online highscore list. Compete for the highest score against players from all over the internet!

it can be found
here